Responses

He did ask permission to enter the house first so technically everyone is at fault. The alfa is inocente and naive and always forgets things. The omega lied about his condition and even do he had his "heat" he let the dude enter his house and then act about liking sex and put himself in danger. So here everyone is at fault
He purposely went to the omegas home, took advantage of him during his heat (from the alphas view) forcibly paired him, and is using him regardless of how the Omega feels. He's scum